fix build error on windows

[AvenSun]

sctp_output.c
L:\usrsctplib\netinet\sctp_output.c(14823): error C2220: the following warning is treated as an error
L:\usrsctplib\netinet\sctp_output.c(14823): warning C4703: potentially uninitialized local pointer variable 'inp' used
L:\usrsctplib\netinet\sctp_output.c(14827): warning C4703: potentially uninitialized local pointer variable 'asoc' used

[tuexen]

Can you show me a possibility how the variable can be use uninitialized? Right now my understanding is that this is a false positive of the Windows compiler. Neither gcc nor clang nor other static code analyzers report a problem...

[AvenSun]

Hi, @tuexen
actually there's no modification of the code.
Just pull and build as a static library on windows via visual studio 2019.

If we don't initialize these two variables during its declaration,
visual studio will raise an error and interrupt the compilation process.
It might be a false positive of visual studio.
I 've no idea why the other uninitialized variables didn't result in this error.
but I think initialization might be more straightforward compared to change the setting of visual studio.

[garbear]

This fixes building on win32/win64/UWP32/UWP64/UWP-arm for me.